Pre-requisite SOP: Scale Checking and Calibration
Dial Scales:
Be careful handling scales – they are fragile and EXPENSIVE!
They can be easily damaged by being dropped or banged around.
Carry dial scales with one hand holding the bottom and the other holding on to the body – not holding by the pan.
All scales need to be used on a stable, level surface.
Dial scales can stick a bit at times – repeat the check a few times to see if problems resolve.
A calibration check needs to be done for each scale used at the beginning of the work or at least once per shift.
See instructions below for how to calibrate.
If the calibration on dial scales needs to be corrected, a small adjustment can be made with the calibration knob under the pan.
You will not need to wind the knob a huge amount. If a small adjustment does not do the trick, ask a supervisor for help.
Digital Scales:
Be careful handling scales – they are fragile and VERY EXPENSIVE!
If they get dropped or banged around, they will be destroyed instantly.
Carry digital scales right side up with two hands on either side of the base.
Do not squeeze down on the pan or place overly heavy objects on the scale – it will destroy the balance.
The maximum weight is written on the scale – DO NOT exceed the maximum.
Digital scales need to be checked for drift or total malfunction.
If the weights are inconsistent or the scale does not turn on at all, check the batteries.
See instructions below for how to calibrate.
If a consistent pattern of error appears, make sure the scale is level with nothing stuck under any feet.
Scale Calibration:
Get the scale to the place where you will be working.
Choose the correct test weight for the package size you are planning to make
Test weights available are 100g, 500g, 5lb., 10lb.
100g is used for 60-250g package weights.
500g is used for 1-2lb. package weights.
5lb. and 10lb. are used for product bulk bags.
For dial scales, make sure the pan is clear of debris and dry. Allow it to come to zero.
For digital scales; turn it on, and re-zero if needed.
If the scale can’t reach zero, it may be faulty or need calibration (calibration means adjusting to measure correctly).
If the scale starts off at zero, then apply the test weight to the centre of the pan. The scale should read the correct weight.
If the scale reads something other than the correct weight, it needs adjustment. Most dial scales have a knob on top under the pan to make adjustments with. A small adjustment should be adequate.
Remove the test weight from the pan. The scale should return to zero. Again, make an adjustment if needed.
Put the weight back on a corner of the pan this time. Again, it should read correctly and restore to zero when the weight is removed.
The scale should be checked with weight standards on the centre and all four corners of the pan in turn during each calibration check.
It should weigh correctly for each location on the pan.
Make adjustments accordingly and ask a supervisor for help if any part of the process shows unexpected results.
The scales must be accurate to be used for packing food.
If the scale is not working properly, stop using it and tell the supervisor. Then get a different scale to use.
– SOP Scale Checking and Calibration (revised )